Thanks to the efficient turbocharged, common-rail, direct fuel-injection diesel engine, the concept car is still very fuel-efficient.

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Diesel engine technology took a huge leap with the use of common-rail direct injection (CDI) in the 1990s.

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In 1887 Congress designated rail a common-carrier service.

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The officers are common fixtures on the new rail line, which opened last year, and walk through the train cars, issuing tickets for passengers who haven't paid their fare.

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